Many modern electronic devices process location data such as location names and geographic coordinates of locations. As an example, navigation devices are configured to calculate a route from a start location to a target location based on geographic coordinates of the locations involved. The geographic coordinates of the start location are typically derived from the output of a positional sensor. The geographic coordinates of the target location, on the other hand, can be determined based on user input.
Some navigation devices are configured to prompt a user for characters that identify a name of the target location. The navigation device then determines matches between the characters input by the user and location names in a database and presents the matching location names for target location selection. When the user confirms a presented location name as target location, the navigation device retrieves geographic coordinates associated therewith as input for a route calculation algorithm.
The search for target locations based merely on location names is cumbersome in various respects. Often, there exist multiple locations with the same target name. In such cases the name search has to be complemented by other identifiers such as the ZIP code of the desired target location. That ZIP code may, however, not be known to the user. Moreover, conventional databases covering whole countries or even continents contain a larger number of location names. As such, the character matching operation is time consuming, which leads to an unsatisfying user experience.
DE 199 29 425 A teaches a navigation device with an improved target location selection function. Here, a user is permitted to move a rectangular frame along predefined fields on a visualized map. When the frame has been moved to a map field that comprises the target location and when the user has confirmed the frame position, the location names of all locations lying within the selected map field are determined from a database and listed next to the visualized map. The user may then either select one of the listed location names using a cursor or, alternatively, input one or more characters. In response to a character input, the list is thinned out to location names starting with such characters. The thinned out list is again presented to the to user for target location selection.